Subordinated Debentures And Trust Preferred Securities (Narrative) (Details) (USD $)			3 Months Ended
	Mar. 31, 2014 item	Dec. 31, 2013	Mar. 31, 2014 CenBank Trust I [Member]	Mar. 07, 2013 CenBank Trust I [Member]	Feb. 22, 2013 CenBank Trust II [Member]	Apr. 15, 2014 CenBank Trust III [Member]	Mar. 31, 2014 CenBank Trust III [Member]	Apr. 07, 2014 Guaranty Capital Trust III [Member]	Mar. 31, 2014 Guaranty Capital Trust III [Member]	Mar. 31, 2014 Minimum [Member]	Mar. 31, 2014 Maximum [Member]
Subordinated Borrowing [Line Items]
Balance of subordinated debentures outstanding	$ 25,774,000	$ 25,774,000					$ 15,464,000		$ 10,310,000
Subordinated debentures outstanding weighted average cost, percent	3.07%	3.07%
Prepayment Penalty			629,000
Current Rate				10.60%	10.20%	2.88%	2.89%	3.33%	3.34%
Subordinated debenture maturity in years	30 years
Trust preferred securities	25,000,000
Number of subordinated debentures issued	2
Debentures callable to subsequent time period in years										5 years	10 years
Subordinated debt, unpaid interest	198,000	202,000
Percent of Tier 1 capital, maximum	25.00%
Securities issued by the trusts qualify as Tier 2 capital threshold, percent	25.00%
Trusts' securities qualified as Tier 1 capital	25,000,000
Limit on total assets to qualify as Tier 1 capital	15,000,000,000
Total assets	$ 1,961,392,000	$ 1,911,032,000									$ 15,000,000,000